/*++ 

Copyright (c) 2004, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials                          
are licensed and made available under the terms and conditions of the BSD License         
which accompanies this distribution.  The full text of the license may be found at        
http://opensource.org/licenses/bsd-license.php                                            
                                                                                          
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,                     
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.             

Module Name:

  Cpu.h

Abstract:

  CPU Architectural Protocol as defined in Tiano

  This code abstracts the DXE core from processor implementation details.

--*/

#ifndef _ARCH_PROTOCOL_CPU_H_
#define _ARCH_PROTOCOL_CPU_H_

#include EFI_PROTOCOL_DEFINITION (DebugSupport)

#define EFI_CPU_ARCH_PROTOCOL_GUID \
  { 0x26baccb1, 0x6f42, 0x11d4, {0xbc, 0xe7, 0x0, 0x80, 0xc7, 0x3c, 0x88, 0x81} }

EFI_FORWARD_DECLARATION (EFI_CPU_ARCH_PROTOCOL);

typedef enum {
  EfiCpuFlushTypeWriteBackInvalidate,
  EfiCpuFlushTypeWriteBack,
  EfiCpuFlushTypeInvalidate,
  EfiCpuMaxFlushType
} EFI_CPU_FLUSH_TYPE;

typedef enum {
  EfiCpuInit,
  EfiCpuMaxInitType
} EFI_CPU_INIT_TYPE;

typedef
VOID
(EFIAPI *EFI_CPU_INTERRUPT_HANDLER) (
  IN EFI_EXCEPTION_TYPE                 InterruptType,
  IN EFI_SYSTEM_CONTEXT                 SystemContext
  );

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_FLUSH_DATA_CACHE) (
  IN EFI_CPU_ARCH_PROTOCOL              * This,
  IN EFI_PHYSICAL_ADDRESS               Start,
  IN UINT64                             Length,
  IN EFI_CPU_FLUSH_TYPE                 FlushType
  );

/*++

Routine Description:

  This function flushes the range of addresses from Start to Start+Length 
  from the processor's data cache. If Start is not aligned to a cache line 
  boundary, then the bytes before Start to the preceding cache line boundary 
  are also flushed. If Start+Length is not aligned to a cache line boundary, 
  then the bytes past Start+Length to the end of the next cache line boundary 
  are also flushed. The FlushType of EfiCpuFlushTypeWriteBackInvalidate must be 
  supported. If the data cache is fully coherent with all DMA operations, then 
  this function can just return EFI_SUCCESS. If the processor does not support 
  flushing a range of the data cache, then the entire data cache can be flushed.

Arguments:

  This       - The EFI_CPU_ARCH_PROTOCOL instance.
  Start      - The beginning physical address to flush from the processor's data 
               cache. 
  Length     - The number of bytes to flush from the processor's data cache. This 
               function may flush more bytes than Length specifies depending upon 
               the granularity of the flush operation that the processor supports.
  FlushType  - Specifies the type of flush operation to perform.
  
Returns: 

  EFI_SUCCESS       -  The address range from Start to Start+Length was flushed from 
                       the processor's data cache.
  EFI_UNSUPPORTEDT  -  The processor does not support the cache flush type specified 
                       by FlushType.
  EFI_DEVICE_ERROR  -  The address range from Start to Start+Length could not be flushed 
                       from the processor's data cache.
                       
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_ENABLE_INTERRUPT) (
  IN EFI_CPU_ARCH_PROTOCOL              * This
  );

/*++

Routine Description:

  This function enables interrupt processing by the processor. 

Arguments:

  This  - The EFI_CPU_ARCH_PROTOCOL instance.
    
Returns: 

  EFI_SUCCESS       -  Interrupts are enabled on the processor.
  EFI_DEVICE_ERROR  -  Interrupts could not be enabled on the processor.
                       
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_DISABLE_INTERRUPT) (
  IN EFI_CPU_ARCH_PROTOCOL              * This
  );

/*++

Routine Description:

  This function disables interrupt processing by the processor.

Arguments:

  This  -  The EFI_CPU_ARCH_PROTOCOL instance.
    
Returns: 

  EFI_SUCCESS       -  Interrupts are disabled on the processor.
  EFI_DEVICE_ERROR  -  Interrupts could not be disabled on the processor.
                       
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_GET_INTERRUPT_STATE) (
  IN EFI_CPU_ARCH_PROTOCOL              * This,
  OUT BOOLEAN                           *State
  );

/*++

Routine Description:

  This function retrieves the processor's current interrupt state a returns it in 
  State. If interrupts are currently enabled, then TRUE is returned. If interrupts 
  are currently disabled, then FALSE is returned.

Arguments:

  This  -  The EFI_CPU_ARCH_PROTOCOL instance.
  State -  A pointer to the processor's current interrupt state. Set to TRUE if 
           interrupts are enabled and FALSE if interrupts are disabled.  
Returns: 

  EFI_SUCCESS             -  The processor's current interrupt state was returned in State.
  EFI_INVALID_PARAMETER   -  State is NULL.
                       
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_INIT) (
  IN EFI_CPU_ARCH_PROTOCOL              * This,
  IN EFI_CPU_INIT_TYPE                  InitType
  );

/*++

Routine Description:

  This function generates an INIT on the processor. If this function succeeds, then the
  processor will be reset, and control will not be returned to the caller. If InitType is 
  not supported by this processor, or the processor cannot programmatically generate an 
  INIT without help from external hardware, then EFI_UNSUPPORTED is returned. If an error 
  occurs attempting to generate an INIT, then EFI_DEVICE_ERROR is returned.

Arguments:

  This     -  The EFI_CPU_ARCH_PROTOCOL instance.
  InitType -  The type of processor INIT to perform.  
  
Returns: 

  EFI_SUCCESS         -  The processor INIT was performed. This return code should never be seen.
  EFI_UNSUPPORTED     -  The processor INIT operation specified by InitType is not supported 
                         by this processor.
  EFI_DEVICE_ERROR    -  The processor INIT failed.   
                       
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_REGISTER_INTERRUPT_HANDLER) (
  IN EFI_CPU_ARCH_PROTOCOL              * This,
  IN EFI_EXCEPTION_TYPE                 InterruptType,
  IN EFI_CPU_INTERRUPT_HANDLER          InterruptHandler
  );

/*++

Routine Description:

  This function registers and enables the handler specified by InterruptHandler for a processor 
  interrupt or exception type specified by InterruptType. If InterruptHandler is NULL, then the 
  handler for the processor interrupt or exception type specified by InterruptType is uninstalled. 
  The installed handler is called once for each processor interrupt or exception.
  
Arguments:

  This              -  The EFI_CPU_ARCH_PROTOCOL instance.
  InterruptType     -  A pointer to the processor's current interrupt state. Set to TRUE if interrupts 
                       are enabled and FALSE if interrupts are disabled.  
  InterruptHandler  -  A pointer to a function of type EFI_CPU_INTERRUPT_HANDLER that is called
                       when a processor interrupt occurs. If this parameter is NULL, then the handler 
                       will be uninstalled.
Returns: 

  EFI_SUCCESS           -  The handler for the processor interrupt was successfully installed or uninstalled.
  EFI_ALREADY_STARTED   -  InterruptHandler is not NULL, and a handler for InterruptType was 
                           previously installed.
  EFI_INVALID_PARAMETER -  InterruptHandler is NULL, and a handler for InterruptType was not 
                           previously installed.
  EFI_UNSUPPORTED       -  The interrupt specified by InterruptType is not supported.
                    
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_GET_TIMER_VALUE) (
  IN EFI_CPU_ARCH_PROTOCOL              * This,
  IN UINT32                             TimerIndex,
  OUT UINT64                            *TimerValue,
  OUT UINT64                            *TimerPeriod OPTIONAL
  );

/*++

Routine Description:

  This function reads the processor timer specified by TimerIndex and returns it in TimerValue.
  
Arguments:

  This        -  The EFI_CPU_ARCH_PROTOCOL instance.
  TimerIndex  -  Specifies which processor timer is to be returned in TimerValue. This parameter
                 must be between 0 and NumberOfTimers-1.
  TimerValue  -  Pointer to the returned timer value.
  TimerPeriod -  A pointer to the amount of time that passes in femtoseconds for each increment 
                 of TimerValue.
Returns: 

  EFI_SUCCESS           -  The processor timer value specified by TimerIndex was returned in TimerValue.
  EFI_DEVICE_ERROR      -  An error occurred attempting to read one of the processor's timers.
  EFI_INVALID_PARAMETER -  TimerValue is NULL or TimerIndex is not valid.
  EFI_UNSUPPORTED       -  The processor does not have any readable timers.
                    
--*/

typedef
EFI_STATUS
(EFIAPI *EFI_CPU_SET_MEMORY_ATTRIBUTES) (
  IN EFI_CPU_ARCH_PROTOCOL              * This,
  IN  EFI_PHYSICAL_ADDRESS              BaseAddress,
  IN  UINT64                            Length,
  IN  UINT64                            Attributes
  );

/*++

Routine Description:

  This function modifies the attributes for the memory region specified by BaseAddress and
  Length from their current attributes to the attributes specified by Attributes.
  
Arguments:

  This          -  The EFI_CPU_ARCH_PROTOCOL instance.
  BaseAddress   -  The physical address that is the start address of a memory region.
  Length        -  The size in bytes of the memory region.
  Attributes    -  The bit mask of attributes to set for the memory region. 
  
Returns: 

  EFI_SUCCESS           -  The attributes were set for the memory region.
  EFI_ACCESS_DENIED     -  The attributes for the memory resource range specified by 
                           BaseAddress and Length cannot be modified.
  EFI_INVALID_PARAMETER -  Length is zero.
  EFI_OUT_OF_RESOURCES  -  There are not enough system resources to modify the attributes of
                           the memory resource range.   
  EFI_UNSUPPORTED       -  The processor does not support one or more bytes of the memory 
                           resource range specified by BaseAddress and Length. 
                           The bit mask of attributes is not support for the memory resource
                           range specified by BaseAddress and Length.
                                          
--*/

struct _EFI_CPU_ARCH_PROTOCOL {
  EFI_CPU_FLUSH_DATA_CACHE            FlushDataCache;
  EFI_CPU_ENABLE_INTERRUPT            EnableInterrupt;
  EFI_CPU_DISABLE_INTERRUPT           DisableInterrupt;
  EFI_CPU_GET_INTERRUPT_STATE         GetInterruptState;
  EFI_CPU_INIT                        Init;
  EFI_CPU_REGISTER_INTERRUPT_HANDLER  RegisterInterruptHandler;
  EFI_CPU_GET_TIMER_VALUE             GetTimerValue;
  EFI_CPU_SET_MEMORY_ATTRIBUTES       SetMemoryAttributes;
  UINT32                              NumberOfTimers;
  UINT32                              DmaBufferAlignment;
};

/*++

Protocol Description:
  
  The EFI_CPU_ARCH_PROTOCOL is used to abstract processor-specific functions from the DXE
  Foundation. This includes flushing caches, enabling and disabling interrupts, hooking interrupt
  vectors and exception vectors, reading internal processor timers, resetting the processor, and
  determining the processor frequency.

Parameters:

  FlushDataCache            -  Flushes a range of the processor's data cache. If the processor does 
                               not contain a data cache, or the data cache is fully coherent, then this 
                               function can just return EFI_SUCCESS. If the processor does not support 
                               flushing a range of addresses from the data cache, then the entire data 
                               cache must be flushed. 
  EnableInterrupt           -  Enables interrupt processing by the processor. 
  DisableInterrupt          -  Disables interrupt processing by the processor.
  GetInterruptState         -  Retrieves the processor's current interrupt state.
  Init                      -  Generates an INIT on the processor. If a processor cannot programmatically 
                               generate an INIT without help from external hardware, then this function 
                               returns EFI_UNSUPPORTED.
  RegisterInterruptHandler  -  Associates an interrupt service routine with one of the processor's interrupt 
                               vectors. This function is typically used by the EFI_TIMER_ARCH_PROTOCOL to 
                               hook the timer interrupt in a system. It can also be used by the debugger to 
                               hook exception vectors.
  GetTimerValue             -  Returns the value of one of the processor's internal timers.
  SetMemoryAttributes       -  Attempts to set the attributes of a memory region.
  NumberOfTimers            -  The number of timers that are available in a processor. The value in this 
                               field is a constant that must not be modified after the CPU Architectural 
                               Protocol is installed. All consumers must treat this as a read-only field.
  DmaBufferAlignment        -  The size, in bytes, of the alignment required for DMA buffer allocations. 
                               This is typically the size of the largest data cache line in the platform. 
                               The value in this field is a constant that must not be modified after the 
                               CPU Architectural Protocol is installed. All consumers must treat this as 
                               a read-only field.
  
--*/

extern EFI_GUID gEfiCpuArchProtocolGuid;

#endif
